[Musicman]

Well, I had the truck realigned again. It was within factory spec, but the drive axles were thrusting against each other. I know some techs do that on purpose, but my local shop thinks that could have been causing the from end to shimmy back and forth. I'm not so sure that was the problem, but time will tell, I guess. I still have the steering wheel shake. I put 6k miles on the new alignment so far. The tires are certainly wearing differently, but I don't know if they are wearing properly. The ridge formed at the edge of the old uneven wear has smoothed out some. I'll probably run the tires a little longer before I pull them off and set them aside for future drive tire use.

I'm pretty sure I've decided to keep the truck for a few more years, especially since it's paid off, so I'm probably going to have all new steering components (at least kingpins, tie rod ends and bearings) put in sometime in the near future. Had I not just spent $4k on a tow bill and new clutch, I'd probably be doing the from end a little sooner.

As a side note, while I was sitting in the KW dealer in Knoxville (who treated me VERY well and did a great job, by the way) getting my new clutch installed, I spent the day in the drivers' lounge talking to a Canadian leased o/o who went out and spec'd a $189k truck that had been down 33 days for repairs out of the first three months he'd owned it. That made me very glad to be repairing my 916k mile, paid for truck (with lifetime 6 cpm maintenance cost for truck, trailer, APU and tires).

[no_worries]

Originally Posted by Musicman

So far I've had four or five tires in that position, results are always the same, although the Bridgestones wore a little worse than my Yokohama's that I normally run.

Maybe not the tire but the wheel. If you haven't actually checked for an out-of-round condition on the wheel/tire assembly but are just going by the fact that the problem has persisted through several different tires, you've only ruled out the tire (most likely) but not the whole assembly, which includes the wheel. An out-of-round or bent wheel would distort the tire causing the same symptom as on OOR tire. Might be worth looking at.

[Musicman]

Originally Posted by no_worries

Maybe not the tire but the wheel. If you haven't actually checked for an out-of-round condition on the wheel/tire assembly but are just going by the fact that the problem has persisted through several different tires, you've only ruled out the tire (most likely) but not the whole assembly, which includes the wheel. An out-of-round or bent wheel would distort the tire causing the same symptom as on OOR tire. Might be worth looking at.

The wheels that are on the steers now actually come from the right front drive position about 10 months ago. I noticed irregular wear on the steers after being on the road for a couple weeks and didn’t plan on being home for two or three more, so I had the TA in Moriarty, NM swap the wheels to save the tires as much as possible without paying the $200 it’d have cost to have them dismount and remount the tires. I don’t have a “radial runout” setup with dial indicators, but I do always look closely at all my rims when I have the tires off. Today in fact, I replaced my steers and rear axle drives, and I took a pretty close look at them then. One somewhat reliable way of checking the rims is to roll them slowly across a clean and smooth concrete floor and watch for irregularities in the rim. Also, if the rim rolls in a perfectly straight line, there’s a pretty good chance that it is pretty close to round. Nothing beats a set of dial indicators, but I haven’t got that technology yet.

[no_worries]

Originally Posted by Musicman

The wheels that are on the steers now actually come from the right front drive position about 10 months ago. I noticed irregular wear on the steers after being on the road for a couple weeks and didn’t plan on being home for two or three more, so I had the TA in Moriarty, NM swap the wheels to save the tires as much as possible without paying the $200 it’d have cost to have them dismount and remount the tires. I don’t have a “radial runout” setup with dial indicators, but I do always look closely at all my rims when I have the tires off. Today in fact, I replaced my steers and rear axle drives, and I took a pretty close look at them then. One somewhat reliable way of checking the rims is to roll them slowly across a clean and smooth concrete floor and watch for irregularities in the rim. Also, if the rim rolls in a perfectly straight line, there’s a pretty good chance that it is pretty close to round. Nothing beats a set of dial indicators, but I haven’t got that technology yet.

If you've swapped wheels during the time the problem was occurring, I guess that's not the problem. I hate front end issues!

[Bandit102too]

Ever figure it out? I'm fighting the steering wheel shake with my '06 387. Put brand new rims and tires on 10,000 miles ago and the shake is back. Centramatics make no difference at all.

[Musicman]

Originally Posted by Bandit102too

Ever figure it out?

A local shop tried adjusting the thrust (alignment of the drive axles). They were adjusted so that one axle was thrusting slightly to one side and the second axle was thrusting slightly the other way. It wasn't enough to cause any irregular wear on the drives, but caused enough shimmy back and forth to be felt in the steering wheel. The shake is gone, but I'm still having the steer tire wear problem. My local Cummins shop said everything looked okay to them, the mom & pop place near my house that does alignments said everything looked good to them as well, but clearly something somewhere is wrong. With close to a million miles on all original steering components, it could be just about anything. I'm fed up with it though and am thinking about replacing kingpins, tie rod ends and bearings. If that doesn't solve the problem, I don't know what will. I dropped it of at Peterbilt today to see if they could do more than just take my money like they often do. I'll know in a couple days.

[Musicman]

Originally Posted by Bandit102too

Ever figure it out? I'm fighting the steering wheel shake with my '06 387. Put brand new rims and tires on 10,000 miles ago and the shake is back. Centramatics make no difference at all.

So I finally got tired of the problem enough that I took the truck to Peterbilt (Sauget, IL). They found what I had already suspected that the steering gearbox was badly worn (we replaced that) and they shimmed the steering axle spring hanger bushings (probably doesn't affect the actual steering or tire wear issue, but I didn't know they could be shimmed). I've only put 8k miles on the truck since I picked it up, but it drives like a completely different vehicle now. I have less vibration in the front end (this is obvious by the reduced vibration that is visible in the fender mounted blind spot mirror) and it I can take my hands off the wheel and it will track straight for as much as a mile. I'm really hoping that this has solved the wear problem, but I wont know until the end of November. By then I'll have about 25k on the truck, post repair and would have seen some tire shoulder wear by that point before the repair.

[Bandit102too]

Well shoot. I've replaced my spring bushings and mounts, replaced the steering box too. Still have my shake, still runs tires perfectly for 80,000 miles and then just starts wiping them out within a couple of weeks. Its always been that way, always. The shake has just been in the last year though.

I was way way way down south in Illinois Friday. About as way far south as you can get.

[Musicman]

Originally Posted by Bandit102too

Well shoot. I've replaced my spring bushings and mounts, replaced the steering box too. Still have my shake, still runs tires perfectly for 80,000 miles and then just starts wiping them out within a couple of weeks. Its always been that way, always. The shake has just been in the last year though.

I was way way way down south in Illinois Friday. About as way far south as you can get.

Well you were probably near my house. I'm about 45 miles north of Paducah.

After replacing the steering box and having the spring hangers shimmed (yes, I know the spring hangers have little or nothing to do with my problem), the tire wear has gotten better. The shake is gone, but the wear is still showing up around the 25k mile point, but it's now only on the left steer outside shoulder and nowhere near as bad as it was. My APU took a dump on me and I'm buying a new TriPac Evolution, but as soon as I recover from that and the holidays, I plan on going ahead and replacing the bearings, tie rod ends and kingpins. They've got a million miles on them, so I figure it's time. I bet that solves my problem.

[Musicman]

Originally Posted by Bandit102too

Well shoot. I've replaced my spring bushings and mounts, replaced the steering box too. Still have my shake, still runs tires perfectly for 80,000 miles and then just starts wiping them out within a couple of weeks. Its always been that way, always. The shake has just been in the last year though.

I was way way way down south in Illinois Friday. About as way far south as you can get.

Well you were probably near my house. I'm about 45 miles north of Paducah.

After replacing the steering box and having the spring hangers shimmed (yes, I know the spring hangers have little or nothing to do with my problem), the tire wear has gotten better. The shake is gone, but the wear is still showing up around the 25k mile point, but it's now only on the left steer outside shoulder and nowhere near as bad as it was. My APU took a dump on me and I'm buying a new TriPac Evolution, but as soon as I recover from that and the holidays, I plan on going ahead and replacing the bearings, tie rod ends and kingpins. They've got a million miles on them, so I figure it's time. I bet that solves my problem.